METHOD FOR OPERATING A WORKPLACE OF A DISHWASHING MACHINE AND DISHWASHING MACHINE

Description

[0001] The present invention relates to a method for operating a working station of a winding machine, in which a yarn is rewound from a bobbin having a spinning head onto a spool by means of a winding device, wherein a yarn balloon forming between the spinning head and the spool during the rewinding process is limited at least in one width direction by means of a balloon limiting device. The balloon limiting device comprises at least one balloon limiter with a yarn guiding surface. The The yarn guide surface has a certain distance to a rotational axis of the spinning sleeve, at least in one working position of the balloon limiter or at least during the rewinding of the first part of the yarn. on.

[0002] The invention further relates to a method for operating a working station of a winding machine, wherein the balloon limiting device comprises a first balloon limiter with a first yarn guide surface, wherein the first yarn guide surface of the balloon limiter has at least in one working position a first distance to a rotation axis of the spinning sleeve, wherein a first part of the yarn located on the spinning sleeve is wound onto the winding sleeve, wherein the yarn balloon is limited by means of the first yarn guide surface.

[0003] Finally, the invention relates to a working station of a winding machine for rewinding a yarn from a bobbin onto a spool by means of a winding device with a balloon limiting device for limiting a yarn balloon that forms between the spinning bobbin and the spool during the rewinding process at least in a width direction, wherein the balloon limiting device includes a first balloon limiter with a first yarn guide surface which has a first distance to a rotation axis of the spinning bobbin at least in one working position of the first balloon limiter, and with a control device.

[0004] Winding machines are used to rewind yarn from wound spindles, such as those from a ring spinning machine, onto a bobbin, creating larger bobbins (usually called cross bobbins). This is necessary for the subsequent processing of the yarn, as spindles typically contain relatively little yarn. Winding machines have numerous winding stations where rewinding operations largely take place independently. During the rewinding process, the yarn from individual spindles is sequentially spliced ​​together by a splicer to form a single, continuous yarn. The rewinding process on the winding machine is also used to remove yarn defects that occurred during the spinning process on an upstream spinning machine, using a yarn cleaner.

[0005] During the rewinding process from the spinning helix to the bobbin, a yarn balloon forms between the unwinding position (where the spinning helix is ​​located during the rewinding process) and a yarn guide located downstream of the spinning helix in the yarn direction. This yarn balloon forms due to centrifugal forces acting on the yarn as it is unwound from the spinning helix. The larger the radius of the yarn balloon during the rewinding process, the greater the yarn tension in the area of ​​the yarn balloon. Therefore, numerous attempts have been made to influence or limit the yarn balloon in order to keep the yarn tension as low as possible during the rewinding process and thus minimize the number of yarn breaks and the risk of impaired yarn quality.

[0006] From DE 10 2006 052 826 A1, a winding machine with multiple workstations, each with a balloon limiting device, is known. The balloon limiting device is adjustable in the vertical direction so that it can be moved downwards during the winding process, following the unwinding progress of the spinning head. The balloon limiting device comprises a tube that is continuously advanced vertically during the winding process according to the position of the head cone, such that the radial distance between the tube and the head cone remains almost constant. Furthermore, the balloon limiting device comprises a second tube that is advanced vertically depending on the signals from a yarn tension sensor. The aim is to reliably establish a so-called single-thread balloon throughout the entire winding process, even at very high winding speeds. The device is comparatively complex in its design.Furthermore, depending on the winding state of the bobbin, comparatively high thread tensions can still occur. JP H05 078016 A discloses a series of balloon limiters arranged one above the other, which are closed sequentially from top to bottom. As is usual in the prior art, the closing occurs depending on the amount of yarn already unwound. According to another embodiment, as in DE 10 2006 052 826 A1, a balloon limiter is continuously advanced downwards as the winding decreases. For this purpose, the upper end of the winding on the bobbin is detected, for example, by means of an optical sensor.

[0007] US patent 5,161,749 A1 also discloses such a continuous tracking of a balloon limiter with decreasing remaining winding. Here, too, the winding state is detected in the usual manner using an optical sensor.

[0008] EP 3 950 551 A1 falls under Article 54(3) EPC and discloses a balloon limiter that can be moved from a rest position to a working position. During unwinding, the yarn pull-off force is measured by means of a yarn tension sensor. First, a portion of the yarn is unwound. If a certain value of the yarn pull-off force is exceeded, the balloon limiter is moved from the rest position to the working position, and then a second portion of the yarn is unwound.

[0009] The object of the present invention is therefore to propose a method for operating a working station of a winding machine which enables winding at a winding speed that is as constant as possible. Furthermore, a working station of a winding machine is to be proposed.

[0010] The problem is solved by a method and a job with the features of independent patent claims.

[0011] In a method for operating a working station of a winding machine, yarn is rewound from a bobbin having a spinning head onto a spool by means of a winding device, wherein a yarn balloon forming between the spinning head and the spool during the rewinding process is limited at least in one width direction by means of a balloon limiting device. The balloon limiting device comprises at least one balloon limiter with a yarn guide surface, which can be moved from a rest position to a working position, wherein the yarn guide surface in the working position of the at least one balloon limiter has a certain distance from an axis of rotation of the spinning head. A first portion of the yarn located on the spinning head is rewound onto the spool, and a measured quantity representing the yarn take-off force of the yarn is recorded.It is provided that, upon detection of an increase in the yarn take-up force by a predetermined value, at least one balloon limiter of the balloon limiting device is moved from the rest position to the working position, and that then a second part of the yarn located on the spinning sleeve is rewound onto the spooling sleeve, whereby the yarn balloon is limited by means of the yarn guide surface.

[0012] The working position is the position the balloon limiter assumes during rewinding, in which it confines the yarn balloon. The resting position, on the other hand, is a position in which the balloon limiter does not confine the yarn balloon. The resting position can also be a head-changing position, allowing the empty spinning head to be exchanged for a fully wound one. However, it is also possible for the balloon limiter to be moved to a different head-changing position than the resting position.

[0013] The axis of rotation is, incidentally, the central longitudinal axis of the normally rotationally symmetrical spinning spool. However, the spinning spool does not rotate during the rewinding process.

[0014] Similarly, the distance of the yarn guide surface to the axis of rotation refers to the minimum distance of the yarn guide surface to the axis of rotation. The yarn guide surface can be cylindrical, so that it has the same distance to the axis of rotation everywhere. However, it can also be polygonal or otherwise irregularly shaped. In this case, the term "distance" refers to the smallest distance of the yarn guide surface to the axis of rotation.

[0015] In a second method for operating a winding machine's workstation, the balloon limiting device comprises a first balloon limiter with a first yarn guide surface. A first portion of the yarn located on the spinning tube is rewound onto the winding tube, the yarn balloon being limited by the first yarn guide surface, and a measured quantity representing the yarn take-off force is recorded. At least during the rewinding of the first portion of the yarn, the first yarn guide surface of the balloon limiter maintains a first distance from a rotational axis of the spinning tube.It is proposed that, upon detection of an increase in the yarn take-off force by a predetermined value, the first distance of the first yarn guide surface to the rotation axis of the spinning spool is reduced, and that a second part of the yarn located on the spinning spool is then rewound onto the spooling spool, whereby the yarn balloon is limited by means of the first yarn guide surface with a reduced distance to the rotation axis.

[0016] Alternatively, in this second method, it is proposed that upon detection of an increase in the yarn take-off force by a predetermined value, at least a second balloon limiter of the balloon limiting device with a second yarn guide surface is moved from a rest position, in which it does not limit the yarn balloon, to a working position, in which it limits the yarn balloon, and that then a second part of the yarn located on the spinning sleeve is rewound onto the spooling sleeve, whereby the yarn balloon is limited by means of the second yarn guide surface.

[0017] In direct measurement of the yarn take-off force, an increase in the yarn take-off force by a predetermined value is detected when the yarn take-off force increases by a predetermined absolute or percentage value compared to a baseline value. In the indirect measurement according to the invention, which involves evaluating the position of a yarn tensioner, an increase in the yarn take-off force by a predetermined value can also be detected when the yarn tensioner travels a predetermined distance or reaches a predetermined position. The predetermined value can, for example, be set by an operator based on experience and stored in a control device of the winding machine. However, the predetermined value can also be obtained and set by the winding machine, in particular by a control device of the winding machine, through a self-learning process based on the evaluation of previous unwinding processes.It is also possible that the winding machine only suggests the predetermined value and that it still needs to be confirmed by the operator.

[0018] All these methods share the common feature that, depending on the yarn take-off force, a yarn guide surface is brought into contact with the yarn, or the contact of a yarn guide surface with the yarn is intensified. This can be achieved by moving a balloon limiter from a rest position to an operating position, or by reducing the distance of a yarn guide surface to the axis of rotation of the spinning spool. The additional or intensified contact of the yarn guide surface thus only occurs when and if the increase in yarn take-off force necessitates it. It is advantageous to initially wind without a balloon limiter or with only one yarn guide surface acting on the yarn. By "activating" or "intensifying" one or more yarn guide surfaces depending on the yarn tension force, it is then possible to keep the yarn take-off force largely constant throughout the winding process.This allows the coil sleeve to be wound with a largely constant winding tension, enabling the production of high-quality coils. It also makes it possible to wind at a largely constant, comparatively high operating speed throughout the entire winding process. Continuously following the winding state of the coil, as required in the prior art, is therefore unnecessary.

[0019] Within the scope of the invention, it is also possible that during the rewinding process additional yarn guide surfaces or additional balloon limiters are "switched on" several times depending on the yarn take-off force and / or that the distance between one or more yarn guide surfaces already acting on the yarn is reduced several times depending on the yarn take-off force.

[0020] A winding machine is further proposed for rewinding yarn from a bobbin containing a spinning head onto a spool by means of a winding device. The winding machine includes a balloon limiting device for limiting a yarn balloon forming between the spinning head and the spool during the rewinding process, at least in one lateral direction. The balloon limiting device comprises a first balloon limiter with a first yarn guide surface, which maintains a first distance from a rotational axis of the spinning head, at least during the rewinding process. The winding machine also includes at least one detection device for detecting a measured quantity representing the yarn take-off force, and a control device connected to the at least one detection device. In this winding machine, the control device is connected to the balloon limiting device.The first balloon limiter of the balloon limiting device can be moved from a rest position, in which it does not limit the yarn balloon, to a working position, in which it limits the yarn balloon, depending on a signal from the at least one detection device.

[0021] Alternatively, at this workstation, it is provided that the first distance of the first yarn guide surface to the rotation axis of the spinning spool can be reduced depending on a signal from the detection device.

[0022] According to a further embodiment, in addition to or as an alternative to the two aforementioned embodiments, this work station provides that the balloon limiting device includes at least a second balloon limiter with a second yarn guide surface, which can be moved from a rest position to a working position depending on a signal from the at least one detection device.

[0023] As previously described, at such a workstation, depending on the yarn take-up force, the influence of a yarn guide surface on the yarn can be "activated" once or several times during the rewinding process in order to keep the yarn take-up force largely constant throughout the winding process. Such a workstation also advantageously allows for winding at a constant working speed.

[0024] Since continuous adjustment of the balloon limiting device to the winding state of the bobbin is not required, the work area can be designed in a simple and cost-effective manner. With the method and the device according to the third embodiment, it is advantageous if the second yarn guide surface, in the working position of the second balloon limiter, has a second distance to the rotational axis of the spinning bobbin that is smaller than the first distance. The bobbins coming from the ring spinning machine are generally unwound in stages, so that the spinning bobbin is gradually freed from top to bottom. The yarn balloon therefore becomes progressively larger during the unwinding process.If the second yarn guide surface is located closer to the axis of rotation of the spinning spool than the first, the yarn balloon can be advantageously constricted more strongly with the second yarn guide surface than with the first. It is also advantageous if, to detect an increase in the yarn take-off force by a predetermined value, a limit value for F, the measured quantity representing the yarn take-off force, is defined, and if, upon exceeding this limit value, the respective balloon limiter is moved to its operating position (A) and / or the distance between the respective yarn guide surfaces is reduced. The limit value can be defined by a specific position of the yarn tensioning element.

[0025] It is also advantageous if, to detect an increase in yarn pull-off force by a predetermined value, a permissible fluctuation range is defined for the measured quantity representing the yarn pull-off force. If this fluctuation range is exceeded, the balloon limiter is moved into its operating position and / or the distance is reduced. The fluctuation range can be a permissible deviation of the yarn pull-off force from a previous measured value. If the current measured value leaves this defined tolerance band around the previous measured values, the respective balloon limiter can be moved into its operating position or the distance of the respective yarn guide surface can be reduced.

[0026] It is proposed that the position and / or travel of a tensioning element of a yarn tensioner be used as the measured variable representing the yarn pull-off force. The yarn tensioner is typically controlled or regulated based on the pull-off force; that is, it opens further when the yarn pull-off force increases and closes further when the yarn pull-off force decreases. Therefore, the position or travel of the tensioning element of the yarn tensioner is, at least as long as the yarn tensioner has not yet reached its end positions, a measured variable representing the yarn pull-off force and can be used to trigger the activation of a yarn guide surface.

[0027] It is therefore advantageous if the position of the clamping element is detected by means of a proximity switch, in particular an optical sensor. Likewise, it is advantageous at the work site if at least one detection device is a proximity switch, in particular an optical sensor. Alternatively, inductive, capacitive, magnetic, or other proximity switches are of course also suitable.

[0028] Alternatively, it is advantageous at the workplace if the adjustment path of the clamping element is recorded by means of a displacement sensor.

[0029] According to an alternative embodiment of the method, it is advantageous if the adjustment travel of the tensioning element is determined by evaluating a control variable and / or measuring a load variable of a drive of the yarn tensioner, in particular the tensioning element. For example, the number of steps of a stepper motor could be detected if the yarn tensioner is moved by means of a stepper motor. Likewise, the adjustment travel could also be determined from currents, voltages, or other load variables of the yarn tensioner's drive. In this case, the drive control unit at the work site constitutes at least one detection device.

[0030] Furthermore, it is advantageous if the first balloon restrictor and / or at least one second balloon restrictor is a balloon constriction ring. This ring need not necessarily be circular, but can also have a polygonal or other irregular shape. Likewise, the first and / or second balloon restrictor could also be tubular structures. The balloon restrictor(s) can be completely closed or have an opening. Likewise, the balloon restrictor(s) can be designed to be divisible.

[0031] Advantages arise if the first and / or at least one second balloon limiter has at least two limiting elements that can be moved from a first position to a second position. For example, the limiting elements can assume the first position in a rest position of the balloon limiter and the second position in a working position. It is also possible for the limiting elements to assume the first position to form the yarn guide surface at the first distance from the axis of rotation of the spinning spool, and to assume the second position to form the yarn guide surface at the second distance from the axis of rotation. More than two limiting elements are also conceivable, which, like a baffle, can form yarn guide surfaces with different diameters.

[0032] Furthermore, it offers advantages if the first and / or at least one second balloon limiter can be moved into a head-changing position. In this case, the head-changing position is different from the resting position.

[0033] However, it is also possible that the rest position simultaneously represents the head-changing position. Moving the first or second balloon limiter into the head-changing position is fundamentally possible in various ways. For example, it is conceivable to open divisible balloon constriction rings sufficiently to allow removal of the head. Alternatively, the balloon limiter, or even the entire balloon limiting device, can be pivoted or moved linearly to be moved from the working or rest position into the head-changing position.

[0034] It is advantageous, for example, if the workstation has a drive device that allows the first balloon limiter and / or the second balloon limiter to be moved along a guide in the direction of the spinning sleeve's axis of rotation. This allows the balloon limiters to be moved, for instance, from a rest position or a head-changing position above the spinning sleeve to a working position at the level of the spinning sleeve.

[0035] In particular, with a balloon limiting device featuring two balloon limiters, it is advantageous if the first and second balloon limiters are mounted on a common support so that they can be moved along the guide. This allows both balloon limiters to be moved together, for example, to a position above the head for changing the head. Likewise, at least one or both balloon limiters can be moved together into their working position.

[0036] Further advantages of the invention are described in the following exemplary embodiments. These show, schematically: Figure 1 a front view of a winding machine with a large number of work stations arranged side by side, Figure 2 a front view of a workstation of a winding machine with a fully enclosed yarn tensioner, Figure 3 the workplace of Figure 2 with a fully opened thread tensioner, Figure 4 a detailed view of a cop and a balloon limiting device after a first execution at a first point in time at the beginning of the rewinding process in a front view, Figure 5 the cops and the balloon limiting device of the Fig. 4 at a second point in time during the rewinding process, Figure 6 the cops and the balloon limiting device of the Fig. 4 at a third point in time during the rewinding process, Figure 7a detailed view of a cop and a balloon limiting device after a second execution at a first point in time at the beginning of the rewinding process in a front view, Figure 8 the cops and the balloon limiting device of the Fig. 7 at a second point in time during the rewinding process, Figure 9 the cops and the balloon limiting device of the Fig. 7 at a third point in time during the rewinding process, Figure 10 a representation of the yarn take-off force during the winding process as well as a limit value for the yarn take-off force, Figure 11 a representation of the yarn take-off force during the winding process as well as a fluctuation range of the yarn take-off force, Figure 12 a detailed representation of a yarn tensioner as well as the recording of the adjustment range of the yarn tensioner in a front view, Figure 13 a balloon limiter with two limiting elements in a rest position in a top view, Figure 14 the balloon limiter of Figure 12in a working position Figure 15 a balloon limiter with two limiting elements in a first position in a top view, as well as Figure 16 the balloon limiter of Figure 15 with the two boundary elements in a second position.

[0037] In the following description of the exemplary embodiments, identical features, or features that are at least comparable in their design and / or function, are designated with the same reference numerals. Furthermore, these features are only explained in detail upon their first mention, while subsequent exemplary embodiments focus solely on the differences compared to those already described. For the sake of clarity, often only one or a few identical components or features are labeled.

[0038] Figure 1Figure 1 shows a schematic front view of a winding machine 1. The winding machine 1 has a plurality of work stations 2 arranged side by side, which are positioned between two frames 21, of which only one is shown here. The work stations 2 are designed to unwind a yarn 3 from a bobbin 22 having a spinning head 4 and to wind it onto a spool 6 by means of a winding device 5. The work stations 2 have numerous working elements for this purpose. These working elements include, among others, a splicer 16, which, after a yarn break, a cleaning cut, or the spinning head 4 running dry, joins a yarn end on the spinning head side to a yarn end on the spool 6 side; a movable suction nozzle for locating a yarn end on the spool 6 side; and a movable suction tube 20 for locating a yarn end on the spinning head side. The work station also has a yarn cleaner 12.

[0039] The winding machine 1 has a central control device 13, which controls the processes at the winding machine 1. In addition, as shown here, each of the workstations 2 can also have its own workstation-specific control device 13, which is connected to the central control device 13 and which controls the processes at the individual workstation 2.

[0040] The yarn 3 wound on the spinning sleeve 4 is pulled off the spinning sleeve 4 and passes a balloon limiter 23, a yarn guide 15 and a yarn tensioner 7, which applies an adjustable yarn take-off force to the running yarn 3 (see figure). Figs. 10 and 11 The yarn tensioner 7 can be controlled accordingly by a control device 13 of the winding station 2. A tensile force sensor 10 is arranged near the winding sleeve 6 to measure the yarn take-off force. Depending on the measured yarn take-off force, the yarn tensioner 7 is adjusted, thereby regulating the yarn take-off force.

[0041] The yarn tensioner 7 is now used based on the Figures 2 and 3 explained in more detail. This shows Figure 2A schematic front view shows a workstation 2. The yarn tensioner 7 is depicted in a closed position GP. During regular winding operation, the yarn tensioner 7 assumes a partially closed position, so that the yarn 3 is deflected multiple times by the yarn tensioner 7 and thus subjected to friction. The yarn take-off force can be influenced by further opening or closing the yarn tensioner 7. The yarn tensioner 7 shown here is designed as a rack tensioner and has two clamping elements 8 that can be moved relative to each other by means of a drive 9. Only one of the two clamping elements 8 can be moved, or both clamping elements 8 can be moved, as shown here. Furthermore, this illustration also indicates a yarn balloon 14 that forms between the spinning tube 4 and the winding tube 6 during the rewinding process.

[0042] Figure 3In contrast, the figure shows the fully open position OP of the yarn tensioner 7, in which the yarn 3 passes through the yarn tensioner 7 freely and without contact. Therefore, no tension is applied to the yarn 3 in this position.

[0043] By means of the yarn tensioner 7, it is possible to regulate the yarn take-off force and keep it largely constant over a wide range of the winding process. However, as soon as the yarn tensioner 7 reaches the fully open position OP or the closed position GP, ​​or as soon as the tensioning element(s) 8 reach their end position, it is no longer possible to influence the yarn take-off force by means of the yarn tensioner 7. In order to keep the yarn take-off force low, the shape and size of the yarn balloon 14 are therefore to be controlled by means of a balloon limiting device 18 (see figure). Fig. 4 ) depending on the yarn take-up force.

[0044] Figure 4Figure 1 shows a first embodiment of a balloon limiting device 18 and a cop 22 with a spinning spool 4. The balloon limiting device 18 has a balloon limiter 23, 26, which is designed here as a balloon constriction ring. The balloon limiter 23, 26 has a yarn guide surface 24, 27, which has a certain distance a1, a2 to a rotation axis 25 of the cop 22 or the spinning spool 4. As the Figure 4 The balloon limiting device 18, which is still removable, is connected to a control device 13, as shown by the dotted line. The control device 13 is in turn connected to a detection device 17, which detects a measured quantity representing the yarn take-up force. Figure 4Figure 2 shows workstation 2, or head 22, at the beginning of the rewinding process. At this point, the spinning spool 4 is still fully wound. Therefore, the forming yarn balloon 14 has a comparatively small height and width at this stage. In this example, the balloon limiter 23, 26 is positioned at a fixed height relative to the spinning spool 4 throughout the entire rewinding process and is not moved along the axis of rotation 25.

[0045] Figure 5 shows Kops 22 or work site 2 of the Figure 4At a later stage of the rewinding process, after a portion of the yarn 3 wound onto the spinning spool 4 has already been unwound, it becomes apparent that the spinning spool 4 is gradually freed of yarn from top to bottom during unwinding, causing the upper head cone to move further downwards. The yarn balloon has thus become larger, so that the yarn guide surface 24, 27 now acts upon the yarn 3 and limits the yarn balloon 14 in the lateral direction. This creates a double balloon, which reduces the centrifugal forces within the yarn balloon 14 and consequently also the yarn take-off force. A first portion of the yarn 3 on the spinning spool 4 is now unwound, with the yarn balloon 14 being limited by the yarn guide surface 24, 27.

[0046] However, especially in the second half of the rewinding process, the yarn take-off force increases despite the limitation imposed by the yarn guide surface 24, 27. If the detection device 17 detects an increase by a predetermined value, the distance a1, a2 between the yarn guide surface 24, 27 and the axis of rotation 25 is reduced as a result of this signal from the detection device 17.

[0047] Figure 6Figure 22 shows the cop and the balloon limiting device 18 of Figures 4 and 5 at a third point in time, at which the distance a1,a2 of the yarn guide surface 24,27 to the axis of rotation 25 has just been reduced. A second part of the yarn 3 is now unwound from the spinning spool 4, whereby the yarn guide surface 24,27 now acts on the yarn balloon 14 with the reduced distance a1,a2. Although the yarn balloon 14 now rises even higher following the winding state of the spinning spool 4, further expansion in the lateral direction is counteracted by the fact that the yarn balloon 14 is now limited by the yarn guide surface 24,27, which is constricted to a smaller distance a1,a2.

[0048] Reducing the distance a1,a2 of the yarn guide surface 24,27 can be achieved, for example, by moving two or more limiting elements 29 of the balloon limiter 23,26 from a first position I to a second position II, as will be shown later with reference to the Figures 15 and 16 is described.

[0049] Figure 7 Figure 1 shows a second embodiment of a balloon limiting device 18. This has a first balloon limiter 23, which is also designed as a balloon constriction ring and has a yarn guide surface 24 at a distance a1 from a rotation axis 25 of the head 22 or the spinning spool 4. Furthermore, the balloon limiting device 18 has a second balloon limiter 26 with a second yarn guide surface 27. The second balloon limiter 26 is designed from a rest position R, which is in the Figures 7 and 8 is shown in a working position A, which is in the Figure 9 The balloon limiting device 18 is also connected to the control device 13, as shown by the dotted line. Figure 7 This again shows the cop 22 at the beginning of the rewinding process, when the spinning spool is still completely wound.

[0050] Figure 8shows Kops 22 or work site 2 of the Figure 7 now, during the unwinding of a first part of the yarn 3 wound on the spinning spool 4, the yarn guide surface 24 of the first balloon limiter 23 acts on the yarn 3 and limits the yarn balloon 14 in the lateral direction. The second balloon limiter 26 is still in its rest position R. To move the second balloon limiter 26 into its working position A (see Fig. 9 ) to transfer, there are in turn limiting elements 29 (see Figs. 13-16 The balloon limiter 26 can be converted from a first position I to a second position II. In the present example, this is achieved by pivoting the limiting elements 29 by 90°. The balloon limiter 26 is thus designed as a divisible balloon constriction ring.

[0051] Figure 9 Finally, it shows the cop 22 and the balloon limiting device 18 of the Figures 7 and 8At a time when the detection device 17 had just detected an increase in the yarn take-off force, the balloon limiting device 18 was again activated by the control device 13 based on the signal from the detection device 17, and the second balloon limiter 26 was moved from its rest position R to its working position A. In working position A, the second yarn guide surface 27 has a distance a2 to the axis of rotation 25, which in this case is less than the distance a1 of the first yarn guide surface 24 to the axis of rotation 25. A second part of the yarn 3 is now unwound from the spinning spool 4, whereby the second yarn guide surface 27 now acts on the yarn balloon 14 at the second distance a2 and limits it.

[0052] In contrast to the one in the Figures 7-9In the illustrated embodiment, the distance a2 of the second balloon limiter 26 to the axis of rotation 25 need not necessarily be smaller than the distance a1 of the first balloon limiter 23. It would also be conceivable that the first yarn guide surface 24 and the second yarn guide surface 27 act on and limit the yarn balloon 14 simultaneously. Depending on the distance between the two balloon limiters 23, 26, a multiple balloon is formed in this case.

[0053] Furthermore, it differs from the presentation of the Figures 7-9 It is also possible that the balloon limiting device 18, like that of the Figures 4-6 has only a single balloon limiter 23,26, which can be moved from a rest position R to a working position A. This can then also be activated upon detection of an increase in the yarn take-off force (see Figures 10 and 11 ) are transferred from the rest position R to the working position A due to a signal from the detection device 17.

[0054] It is also possible for several balloon limiters 23, 26 to be combined in a balloon limiting device 18, which are moved sequentially or partially simultaneously from their rest position R to their working position A upon detection of an increase in the yarn take-off force, or in which the distance a1, a2 to the axis of rotation 25 is reduced upon detection of an increase in the yarn take-off force. The different versions of balloon limiters 23, 26 can also be combined in a single balloon limiting device 18.

[0055] To trigger the transition from rest position R to working position A and / or the reduction of the distance a1,a2, a limit value 28 for the yarn take-off force can, for example, be specified. This is in Figure 10 depicted.

[0056] Finally, it is also possible that the two balloon limiters 23, 26, or even additional balloon limiters 23, 26, are arranged together at the work station 2 in a height-adjustable manner. For this purpose, the balloon limiters 23, 26 can, for example, be arranged on a common support, which is slidably and driveably mounted on a guide extending in the direction of the axis of rotation 25. The balloon limiters 23, 26 can be arranged at a constant height relative to the spinning spool 4 during the rewinding process, but can be moved to a head-change position above the spinning spool to remove an empty spinning spool 4 and replace it with a fully wound one.

[0057] Figure 10This shows the yarn take-off force over the entire rewinding process, or the length of the yarn, as it would behave without the influence of the balloon. It is evident that the yarn take-off force is largely constant during the first half of the rewinding process, while it increases in the second half. Furthermore, it can be seen that towards the end of the rewinding process, particularly in the last third, there is an exponential increase in the yarn take-off force. Since minor fluctuations in the yarn take-off force are generally unproblematic and can usually be compensated for by the yarn tensioner 7, a limit value 28 can be assumed, for example, that is 20% higher than the value of the yarn take-off force in the first half of the rewinding process.

[0058] Alternatively, it is also possible to use not the exceeding of a limit value 28 as the triggering signal, but the exceeding of a fluctuation range 30. This is in Figure 11depicted.

[0059] Since minor fluctuations in yarn take-up force are unproblematic, a permissible fluctuation range of 5–10 N can be defined within a specific comparison period. The yarn take-up force is continuously recorded and compared with previous measurements from the same period. If the permissible fluctuation range of 30 is exceeded, as is the case in Figure 11 As depicted, this is detected by the detection device 17 and a signal is output to the control device 13. Based on this signal, the control device 13 can then activate the reward limiting device 18 to bring an additional balloon limiter 23, 26 into effect or to reduce a distance a1, a2 of the yarn guide surface 24, 27 to the axis of rotation 25.

[0060] According to the invention, it is provided that the yarn take-off force is not measured directly, but rather a measured quantity representing the yarn take-off force. This is in Figure 12 depicted.

[0061] Figure 12 Figure 1 shows a detailed view of a yarn tensioner 7 with two tensioning elements 8 movable by means of a drive 9. As mentioned at the beginning, the drive 9 is controlled by signals from a tensile force sensor 10, which measures the yarn take-off force. The current adjustment path s, which is shown here as an example for the tensioning element 8 shown on the right in the image, or the current position of the tensioning element(s) 8, is therefore an indirect parameter for the yarn take-off force.

[0062] In the present example, a sensor 11 detects whether the clamping element 8 is in its fully open position OP. The closed position GP of the yarn tensioner 7 is also shown in dashed lines. Alternatively, the traveled adjustment distance s could also be detected using a displacement sensor.

[0063] The Figures 13 and 14 Finally, they show a balloon limiter 23, 26, which has two limiting elements 29 that, from a first position I, are in Figure 13 As shown, they can be moved into a second position II, which is in Figure 14The two limiting elements 29 are pivotally mounted for this purpose (however, they are shown broken off in this example). In this example, the balloon limiter 23, 26 is in a rest position R when the limiting elements 29 assume the first position I. In the rest position R, the balloon limiter 23, 26 does not limit the yarn balloon 14. Since in this rest position R the limiting elements 29 are far outwards from the circumference of the head 22, the rest position R can also serve as a head change position.

[0064] In the Figure 14 In the illustrated working position A of the balloon limiter 23, 26, the limiting elements 29, however, assume the second position II. In this position, the limiting elements 29 form a closed balloon constriction ring and can limit the yarn balloon 14.

[0065] Again Figure 14Since the balloon limiter 23,26 remains removable, it is also possible that the diameter of the yarn guide surface 24,27 of the balloon limiter 23,26 is smaller than the outer diameter of the head 22, because the balloon limiter has a rest position R. If this is the case, the balloon limiter 23,26 can only be moved into its working position A when at least an upper part of the spinning sleeve 24 is already exposed.

[0066] The Figures 15 and 16 Figure 23, 26 shows a different embodiment of a balloon limiter with limiting elements 29 that can be moved from a first position I to a second position II. This embodiment of a balloon limiter 23, 26 can be advantageously used to reduce the distance a1, a2 of the yarn guide surface 24, 27 to the axis of rotation 25 of the head 22, or the inner dimension, here the inner diameter, of the yarn guide surface 24, 27. The limiting elements 29 are located in the balloon limiter. Figure 15The limiting elements 29 are in the first position I, in which the yarn guide surface 24, 27 forms a larger diameter. Figure 16 The boundary elements 29, however, are in a second position II, in which the yarn guide surface 24, 27 is constricted and thus has a smaller diameter and consequently a reduced distance a1, a2 to the axis of rotation 25. The distance a1, a2 and the axis of rotation 25 are in the Figures 4 - 6 visible and in the Figures 15 and 16 not shown.

[0067] In the figures described here, the respective balloon limiter 23, 26 is moved from the rest position R to the working position A by moving movable limiting elements 29 from a first position I to a second position II. However, it is also possible that one or more balloon limiters 23, 26 are arranged at the work location 2 so that they are movable overall, for example along the axis of rotation 25, in order to move from their rest position R, which is located, for example, above the head 22 near the yarn guide 15 (see figure). Figures 2 - 9 ) might be arranged to be transferred to their working position A.

[0068] The invention is not limited to the embodiments shown and described. Modifications within the scope of the patent claims are possible. Reference symbol list

[0069] 1 Winding machine 2 Workstation 3 Yarn 4 Spinning sleeve 5 Winding device 6 Winding sleeve 7 Yarn tensioner 8 Tensioning element 9 Drive of the tensioning element 10 Tension sensor 11 Sensor 12 Yarn cleaner 13 Control device 14 Yarn balloon 15 Yarn guide 16 Splicer 17 Detection device 18 Balloon limiting device 19 Suction nozzle 20 Suction tube 21 Frame 22 Head 23 First balloon limiter 24 First yarn guide surface 25 Rotation axis 26 Second balloon limiter 27 Second yarn guide surface 28 Limit value 29 Limiting element 30 Fluctuation range Working position R Resting position a1 First distance a2 Second distance s Adjustment path First position II Second position GP Closed position of the yarn tensioner OP Open position of the yarn tensioner

Claims

1. A method for operating a working station (2) of a winding machine (1), in which a yarn (3) is rewound from a cop (22) having a spinning tube (4) onto a winding tube (6) by means of a winding device (5), wherein a yarn balloon (14) forming between the spinning tube (4) and the winding tube (6) during the rewinding process is delimited at least in a width direction by means of a balloon delimiting device (18), wherein the balloon delimiting device (18) comprises at least one balloon delimiter (23, 26) with a yarn guiding surface (24, 27), which can be transferred from a rest position (R), in which it does not delimit the yarn balloon (14), into a working position (A), in which it delimits the yarn balloon, wherein the yarn guiding surface (24, 27) in the working position (A) of the at least one balloon delimiter (23, 26) has a distance (a1, a2) from an axis of rotation (25) of the spinning tube (4), characterized in that a first part of the yarn (3) located on the spinning tube (4) is rewound onto the winding tube (6), a measuring variable representing the yarn draw-off force is detected, wherein a position and / or an adjustment travel (s) of a tensioning element (8) of a yarn tensioner (7) is detected as the measuring variable representing the yarn draw-off force, upon detection of an increase in the yarn draw-off force by a predetermined value, the at least one balloon delimiter (23, 26) of the balloon delimiting device (18) is transferred from the rest position (R) into the working position (A) and in that a second part of the yarn (3) located on the spinning tube (4) is then rewound onto the winding tube (6), wherein the yarn balloon (14) is delimited by means of the yarn guiding surface (24, 27).

2. A method for operating a working station (2) of a winding machine (1), in which a yarn (3) is rewound from a cop (22) having a spinning tube (4) onto a winding tube (6) by means of a winding device (5), wherein a yarn balloon (14) forming between the spinning tube (4) and the winding tube (6) during the rewinding process is delimited at least in a width direction by means of a balloon delimiting device (18), wherein the balloon delimiting device (18) comprises a first balloon delimiter (23) with a first yarn guiding surface (24), wherein a first part of the yarn (3) located on the spinning tube (4) is rewound onto the winding tube (6), wherein the yarn balloon (14) is delimited by means of the first yarn guiding surface (24), wherein the first yarn guiding surface (24) of the balloon delimiter (23) has a first distance (a1) from an axis of rotation (25) of the spinning tube (4) at least during the rewinding of the first part of the yarn (3), characterized in that a measuring variable representing the yarn draw-off force is detected, wherein a position and / or an adjustment travel (s) of a tensioning element (8) of a yarn tensioner (7) is detected as the measuring variable representing the yarn draw-off force, wherein upon detection of an increase in the yarn draw-off force by a predetermined value, the first distance (a1) of the first yarn guiding surface (24) from the axis of rotation (25) of the spinning tube (4) is reduced and in that a second part of the yarn (3) located on the spinning tube (4) is then rewound onto the winding tube (6), wherein the yarn balloon (14) is delimited by means of the first yarn guiding surface (27) with a reduced distance (a1) from the axis of rotation (25), and / or in that at least one second balloon delimiter (26) of the balloon delimiting device (18) with a second yarn guiding surface (27) is transferred from a rest position (R), in which it does not delimit the yarn balloon (14), into a working position (A), in which it delimits the yarn balloon, and in that a second part of the yarn (3) located on the spinning tube (4) is then rewound onto the winding tube (6), wherein the yarn balloon (14) is delimited by means of the second yarn guiding surface (27).

3. The method according to the preceding claim, characterized in that the second yarn guiding surface (27) in the working position (A) of the second balloon delimiter (26) has a second distance (a2) from the axis of rotation (25) of the spinning tube (4), which is smaller than the first distance (a1).

4. The method according to one of the preceding claims, characterized in that a limit value (28) for the measuring variable representing the yarn draw-off force is defined and upon exceeding the limit value (28), the balloon delimiter (23, 26) is transferred into its working position (A) and / or the distance (a1, a2) is reduced.

5. The method according to one of the preceding claims, characterized in that a permissible fluctuation range (30) of the measuring variable representing the yarn draw-off force is defined and upon exceeding the fluctuation range (30), the balloon delimiter (23, 26) is transferred into its working position (A) and / or the distance (a1, a2) is reduced.

6. A working station (2) of a winding machine (1) for rewinding a yarn (3) from a cop (22) having a spinning tube (4) onto a winding tube (6) by means of a winding device (5), with a balloon delimiting device (18) for delimiting a yarn balloon (14) forming between the spinning tube (4) and the winding tube (6) during the rewinding process at least in a width direction, wherein the balloon delimiting device (18) includes a first balloon delimiter (23) with a first yarn guiding surface (24), which has a first distance (a1) from an axis of rotation (25) of the spinning tube (4) at least during the rewinding, with a yarn tensioner (7) and with a control unit (13), characterized in that at least one detection device (17) for detecting a measuring variable representing the yarn draw-off force is provided, which is in connection with the control unit (13), wherein the detection device detects a position and / or an adjustment travel (s) of a tensioning element (8) of the yarn tensioner (7) as the measuring variable representing the yarn draw-off force, in that the control unit (13) is in connection with the balloon delimiting device (18) and in that upon detection of an increase in the yarn draw-off force by a predetermined value, the first balloon delimiter (23) of the balloon delimiting device (18) can be transferred as a function of a signal of the at least one detection device (17) from a rest position (R), in which it does not delimit the yarn balloon (14), into a working position (A), in which it delimits the yarn balloon (14), or in that upon detection of an increase in the yarn draw-off force by a predetermined value, the first distance (a1) of the first yarn guiding surface (24) from the axis of rotation (25) of the spinning tube (4) can be reduced as a function of a signal of the at least one detection device (17) and / or in that the balloon delimiting device (18) includes at least one second balloon delimiter (26) with a second yarn guiding surface (27), which can be transferred upon detection of an increase in the yarn draw-off force by a predetermined value as a function of a signal of the at least one detection device (17) from a rest position (R), in which it does not delimit the yarn balloon (14), into a working position (A), in which it delimits the yarn balloon.

7. The working station (2) according to the preceding claim, characterized in that the second yarn guiding surface (27) in the working position (A) of the at least one second balloon delimiter (26) has a second distance (a2) from the axis of rotation (25) of the spinning tube (4), which is smaller than the first distance (a1).

8. The working station (2) according to one of the preceding device claims, characterized in that the at least one detection device (17) is a proximity switch or a distance sensor or a detection sensor, in particular an optical sensor (11), or a displacement sensor (11).

9. The working station (2) according to one of the preceding device claims, characterized in that the at least one detection device (17) is a control of a drive (9) of the yarn tensioner (7).

10. The working station (2) according to one of the preceding device claims, characterized in that the first balloon delimiter (23) and / or the at least one second balloon delimiter (26) is a balloon restraining ring.

11. The working station (2) according to one of the preceding device claims, characterized in that the first and / or the at least one second balloon delimiter (23, 26) has at least two delimiting elements (29), which can be moved from a first position (I) into a second position (II).

12. The working station (2) according to one of the preceding device claims, characterized in that the first and / or the at least one second balloon delimiter (23) can be transferred into a cop changing position.